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Symbols used at this site - Boston Piezo
Symbols used at this site - Boston Piezo

... Dielectric Constant: The ratio of the permitivity of the material to the permitivity of free space. The value specified is for the "free" condition (i.e., unclamped and well below the mechanical resonance of the part). Dissipation Factor: A measure of the dielectric losses in the material defined as ...
PT 1.1 - HARMAN Professional Solutions
PT 1.1 - HARMAN Professional Solutions

... backed by Crown’s unequaled Three-Year, NoFault, fully-transferrable warranty that covers everything. With over five decades of experience designing and building rock-solid products, Crown is the standard in amp technology. So check out the affordable, “all-Crown” Power-Tech .1. They are a powerful ...
Datum - Zavod RS za šolstvo
Datum - Zavod RS za šolstvo

... relatively safe method for attaching appliances to a power source. Because a power plug is inserted into the power socket, a power plug is usually referred to as being 'male' whilst the power socket is 'female'. A power plug completes the circuit between power plug power socket the power source and ...
coutant
coutant

... circuitry does not permit changing of components on the P.C.B's without special test facilities, however whole P.C.B. assemblies are available as spares. See parts lists for type numbers. If it is necessary to return power supplies to the Service department please ensure they are adequately packed f ...
Poster
Poster

... A lightweight film known as Kapton with 12 piezoelectric transducers attached was subjected to a frequency range of 1 kHz to 15 MHz of current at 10 volts. The resulting sinusoidal waves produced and sensed by an actuator-sensor pair will be compared to the waves produced and sensed by a different a ...
PDF
PDF

... and power supply unit must be combined. To integrate them into an optimum system (Fig. 1), we developed the following: (1) Software to enable one CPU to control three servo axes simultaneously, an increase from two axes in the conventional system (2) Unitized current sensing resistor for motor curre ...
Calculation of Power factor Correction
Calculation of Power factor Correction

... operate on leading power factor like an over-excited synchronous motor. Phase advancers have two principal advantages. Firstly, as the exciting ampere turns are sup-plied at slip frequency, therefore, ...
BAŞKENT UNIVERSITY
BAŞKENT UNIVERSITY

... In the event of a short-circuits, i. E. U = 0, the total voltage thus already drops across the internal resistance. Variable Resistor (Potentiometer) A 3 pinned variable resistor is like next figures, made of a carbon strip and a slipping pin. So if you have an “A” ohm variable resitor you have two ...
Electric Motor Comparison
Electric Motor Comparison

Module 2 : Transmission Lines Lecture 6 : Loss Less
Module 2 : Transmission Lines Lecture 6 : Loss Less

... Spatial Variation of Current & Voltage The previous equations indicate that the amplitudes of the voltage and current vary as a function of distance on the line. ...
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Rc Circuits mzes

DC939 - LTC2484CDD Evaluation Kit Quick Start Guide
DC939 - LTC2484CDD Evaluation Kit Quick Start Guide

Shop Monitor Unit
Shop Monitor Unit

... This unit is ideal for applications such as connecting individual shop units into a main shopping centre system. The UL shop monitor unit provides a zone of detection with up to 20 Cooper UL conventional detector/bases supported. It also supports a zone of pull stations as well as 2 conventional sou ...
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Essential Performance in a Compact Size
Essential Performance in a Compact Size

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Power Factor Correction Boost Controller

Power Supply for Crookes Tube (Model N99-B10
Power Supply for Crookes Tube (Model N99-B10

... 1. Set both the Main Power and Anode Power (acceleration voltage switch) to OFF, turn the Deflection Dial (deflection voltage adjustment) to the extreme left, set the Polarity Switch to the center position, and connect the AC adapter. 2. Turn the Main Power ON. The red LED lights up indicating that ...
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Connecting Power

DigiMod 2000HV
DigiMod 2000HV

Miniature, Precision Negative Reference
Miniature, Precision Negative Reference

University of North Carolina-Charlotte Department of Electrical and Computer Engineering
University of North Carolina-Charlotte Department of Electrical and Computer Engineering

... should find that Eaf was larger in part c.2 when the reactive power output was higher. If Eaf had not been increased by increasing the field current in the generator, the voltage on the generator bus would have decreased. Use the single phase circuit model of the generator to explain why Eaf must in ...
Analog vs Digital Terminology
Analog vs Digital Terminology

... of a dozen, digitized to the base 10. Decimal, octal, and hexadecimal bases are not uncommon as choices for the base of digitization. Assembly languages are typically written in hexadecimal quantities. Of course, much of the power and simplicity of modern computers follows from the choice of the bas ...
Section 1-2 - Scott Buffett
Section 1-2 - Scott Buffett

Implementation of grid-connected photovoltaic system with power
Implementation of grid-connected photovoltaic system with power

IMC-101 Series
IMC-101 Series

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Decibel

The decibel (dB) is a logarithmic unit that expresses the ratio of two values of a physical quantity, often power or intensity. One of these quantities is often a reference value and in this case the decibel expresses the absolute level of the physical quantity. The number of decibels is ten times the logarithm to base 10 of the ratio of two power quantities, or of the ratio of the squares of two field amplitude quantities. One decibel is one tenth of one bel, named in honor of Alexander Graham Bell; however, the bel is seldom used.The definition of the decibel is based on the measurement of power in telephony of the early 20th century in the Bell System in the United States. Today, the unit is used for a wide variety of measurements in science and engineering, most prominently in acoustics, electronics, and control theory. In electronics, the gains of amplifiers, attenuation of signals, and signal-to-noise ratios are often expressed in decibels. The decibel confers a number of advantages, such as the ability to conveniently represent very large or small numbers, and the ability to carry out multiplication of ratios by simple addition and subtraction. By contrast, use of the decibel complicates operations of addition and subtraction.A change in power by a factor of 10 is a 10 dB change. At the half power point an audio circuit or an antenna exhibits an attenuation of 3dB. A change in voltage by a factor of 10 results in a change in power by a factor of 100, which is a 20 dB change. A change in voltage ratio by a factor of two approximately corresponds to a 6 dB change.The decibel symbol is often qualified with a suffix that indicates the reference quantity that has been used or some other property of the quantity being measured. For example, dBm indicates a reference power of one milliwatt, while dBu is referenced to approximately 0.775 volts RMS.In the International System of Quantities, the decibel is defined as a unit of measurement for quantities of type level or level difference, which are defined as the logarithm of the ratio of power- or field-type quantities.
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